Process for the production of basic steel



Patented Aug. 14, 1923.

. NITED STA lELQ PATENT OFFICE.

RENE BAURET, or PARIS, raanoafassmnoa Tomi soomrn: USINES METAL-LURGIQUES DE LA BASSE LDIBE, or rams, cannon, SIEGE SOCIAL.

,.mocass" ro a Tiin raonucrron or. BASIC sTEnL.

No Drawing.

To all whom it may concern:

Be it known that I, RENE BAURET, citizen of the Republic of France, andresident of Paris, Seine, France (post-oflice address 26" rue Alphonsede Neuville), Paris, have invented a new and useful Process for theProduction of.l3asic Steel, which improvements are fully set forth inthe following specification. I

The present invention relates to a process for the production of basicsteel, and is an improvement in or modification of the inventiondescribed and claimed in the specification of the co-pending applicationfor United States Patent Serial 468,762 hereinafter re terred to as themain patent.

In said main patent there has been described and claimed a process forthe production of basic steel by the treatment in the converter of greypig iron with a silicon content above the normal, which could hithertoonly be treated wastefully if at all, which consists in preparing in orintroducing into'the converter before the pig iron, or the bulk of thepig iron is added, a liquid bath comprising oxides and lime adapted tooxidize the silicon of the pig iron immediately.

According to the present invention the conversion process set forth inthe main patent is utilized, for the production in a basic converter ofhard steels, or semihard steels with a high carbon content, and totallydephosphorized. Without it being necessary to add to the metal,spiegeleisen, pig-iron or other re-carburizing agents.

It has been found. in carrying out the second phase of the operationaccording to the process forming the object of the main patent in thepresence of a calcareous slag rich in oxides of iron. that the newlycharged pig-iron is dephosphorized very rapidly. This dephosphorizationmay be realized in practice before the carbon is entirely oxidized. sothat by taking precautions to regulate the proportions of pig-iron addedin each phase. it is easy to obtain steels, the analyses of which show acontent of 0.50 and 0.60% carbon. with a content of 0.05% phosphorus. Ithas been found in practice that for charges of pig-iron exceeding 70%,(the normal charge of the usual processes.) the pressure of the blastdoes not exceed the pressure attained in ordinary operations Serial No.491,527.

this being in consequence of the very great fluidity of the bathproduced in the second operation. 011 the other hand. projections areentirely eliminated, and nothing prevents the filling of the converterto the maximum limit. It thus becomes possible in practice to increasethe yield in certain apparatus by at least 70%, this figure being liableto variation according to the shape of the converters.

An economic advantage is thus obtained which is very important in themanufacture of hard steels or semi hard steels with high carbon contentand totally dephosphorized.

What I claim and desire to secure by Letters Patent is 1. The processfor the production in a basic converter of hard steels with a highcarbon content and practically dcphosphorized, which consists inpreparing in the converter before the pig iron is added a liquid bathcomprising lime and oxides adapted to dephosphorize the pig iron veryrapidly.

2. The process for the production in a basic converter of hard steelswith a high carbon content and practically dephosphorized, whichconsists in preparing in the con verter before the pig iron is added aliquid bath comprising lime and oxides of iron adapted to dephosphorizethe pig iron very rapidly.

3. The process for the production in a basic converter of hard steelswith a high carbon content and practically dephosphorized, whichconsists in preparing in the converter a liquid bath comprising lime andoxides of iron adapted to dephosphorize the pig iron very rapidly. andadding a predetermined amount of pix. iron.

4. The process for the production in a basic converter of hard steelswith a high carbon content and practically dephospborized, Whichconsists in preparing in the converter a predetermined quantity of aliquid bath comprising lime and oxides of iron adapted to dephosphorizethe pig iron very rapidly. and introducing an abnormal charge of pigiron.

5. The process for the production in a basic converter of hard steelswith a high carbon content and practically dcphosohon ized. whichconsists in preparing in the converter a liquid bath comprising lime andoxides of iron adapted to dephosphorize the pig iron very rapidly, andfilling the converterm thg g;1gg imym limitw ll}; gig irgp.

(s. fiche i-o assf {qr thp'ipgfictgmfiifia basic r onverte r of hardsteels Vl lth 2 L high curlum LUllli'llt and practically dephosphor-'ized, which 'cofisists iirprtafiaring in the @011 \erlel' :1predtermined quahtity of liquid bath comprising lime anc l pxides ofiron adapted to (lephosphoriz'g the pig iron very rapidly and fillingthe converter to the 10 I a; ling; withplg iron.

l: stiiilp'liyw'jiiherqffl have signed this Specification in thepresence of two subscribing witnesses.

- I -RENI IBAURET.

Witnss:

J. LEE MURPHY, 'FERNAND DUFOUR.

